Frequently, patients in nursing homes and hospitals must be monitored when personnel are not present. For instance, patients receiving intravenous injection are left unattended because staff and personnel are needed elsewhere. Typically, the intravenous delivery device is monitored so that when the intravenous solution is depleted, an alarm is sounded to alert the caregiver of this condition. Because most patients are unfamiliar with these devices, the sounding of the alarm can scare the patient and cause them to be frightened and uneasy.
Patients in nursing homes and hospitals must also be monitored when they move about or require assistance when they attempt to sit, stand, and walk. In the past, these patients have had to be immobilized with physical restraints when personnel have not been available to assist or watch them. The use of physical restraints, such as straps and cords, has been found unsuitable in many cases because it is objectionable to the patient and the patient's relatives, and it often results in unnecessary discomfort for the patient.
Several alternative systems have been proposed for notifying a caregiver that a patient is attempting to move. For instance, in U.S. Pat. No. 2,260,715, a normally closed contact switch is placed between the mattress and the box spring on the patient's bed. The weight of the patient in the bed opens the contact switch to prevent activation of an electric light. When the weight of the patient is removed from the bed, the contact switch closes to activate the electric light. If applied to alarms, this system would have the disadvantage of being subject to frequent false alarms, such as when the patient momentarily lifts a significant portion of his weight off the bed to shift position, or when the patient moves to merely sit on the edge of the bed. This system also requires modification of the bed mattresses to insert the contact switch and wires and to insulate the electronic components to minimize the risk of fire, personal injury, and shock.
In U.S. Pat. No. 4,577,185, an alert system is disclosed that uses a built-in call unit or alarm in the wall and a cord having one end plugged into the wall unit and the other end clipped to the patient's clothing. With the cord plugged into the call unit, the alarm is deactivated. As the patient attempts to sit up or move, the attached cord is pulled from the call unit to activate the alarm. This particular system requires that the call unit be horizontally and vertically aligned with the patient to allow the plug to be easily removed from the wall unit. Any misalignment of the cord with the axis of the plug will make it extremely difficult to pull the plug from the call unit and may result in the cord pulled from the patient's clothing. This would render the alarm ineffective and allow the patient to get up. As such, this system is limited to use in a hospital bed. Furthermore, this system requires modification of the wall of the care facility and, if a standard wall-mounted monitor is used, the existing patient call button must be replaced by the alarm cord, which introduces a significant problem.
Another drawback to these systems and to the alarm system used on intravenous solution delivery devices and other devices which require alerting the caregiver of certain conditions is that the sounding of an alarm can easily frighten a patient. This is especially true when a patient is awakening from sleep in a room where the caregiver is not present. When the patient awakens, he can be disoriented and experience apprehension if he is unfamiliar with his surroundings or forgets where he is. The sounding of an alarm will create fear and additional concern in the patient. This can cause the patient to become overly excited and cause harm to himself or others or damage to the facilities. Consequently, there is a need for a monitoring system that will inform, calm, etc., the patient as well as inform the caregiver as to a change in conditions, such as the need to replenish intravenous solution or to attend to a patient who is attempting to move.